The present invention relates to a method for making decorative emblems, plaques, and the like (hereafter generically called "decorative shapes") which have a cured plastic layer over a decorative surface and shapes prepared by that method. More particularly it relates to a method in which a plurality of individual coated shapes are stamped from a single substrate without damaging the plastic coat or deforming the shape during the die cutting operation.
Copending U.S. application Ser. No. 054,548 filed July 5, 1979, now U.S. Pat. No. 4,292,827 discloses a process for mass producing decorative shapes in which a smooth coating of a radiation curable polyurethane composition is applied by flow coating to a foil substrate decorated with a series of designs in the form of individual emblems or plaques and backcoated with a layer of adhesive. Using a cutting die such as shown in FIG. 3 individual shapes are stamped from the substrates by pressing the shape contiguous with the decorative design with a male punch into a female cutting die. This imparts a domed shape to the decorative emblem. While in some instances this dome is of aesthetic value, the depth of the dome is difficult to control and the domed shape is difficult to apply to a flat surface or a surface where the radius of curvature is substantially different than that of the dome. Furthermore, when a dome is imparted to the shape as it is die cut, it is difficult to obtain decorative shapes having a sharply cut vertical edge, occasionally the shape may delaminate, scratch or chip, and there is some edge deformation and slivering of the foil substrate. There is also a tendency for the adhesive to ooze from the substrate and contaminate the female die when it is die cut. All of these drawbacks contribute to a reduction in the weather resistance of the cut shape.
A typical decorative shape produced in accordance with the present invention and the aforementioned U.S. patent is stamped from a laminate including a sheet of aluminum painted or silk-screened on one side with a decorative insignia or graphic which is over coated with a layer of cured polyurethane and coated on the other side with an adhesive composition. The adhesive layer is overlayed with a sheet of release paper. One example of this laminate is shown in FIG. 1. When the cutting die strikes this laminar structure, due to the relative softness of the polyurethane and the adhesive composition in comparison to the aluminum sheet, the coated substrate moves slightly with the cutting edge of the die. This causes the substrate to bow under the face of the male punch. Bowing involves the drawbacks mentioned above. In particular, bowing irreversibly domes the decorative shape and produces a shape with poor edge characteristics, which is subject to delamination and has poor weather resistance.
Thus, there is a need for a method of die cutting shapes having a weather and wear resistant plastic coating which does not dome or delaminate the shape and which yields a sharply cut edge and a shape having good weather resistance.